A road resurfacing unit is disclosed in U.S. Pat. No. 5,795,096 issued Aug. 18, 1998, which uses teeth to rip a gravel road prior to separating coarse material from fine material and depositing the coarse material on the fine material. A difficulty with the design disclosed in the patent is that the teeth tend to wear. While the teeth may be individually replaced, this is time consuming. The inventor has proposed a solution to the wear problem of ground working equipment such as the road resurfacing unit disclosed in U.S. Pat. No. 5,795,096.